Don

[Jim Fisher]

When you do your testing on the beds. Do you do temperture readings at the acrylic? If so , can you post them

[solarmeter®]

Hint:

If the lamps run too hot the UV output will suffer.

If the lamps run too cool the UV output will suffer.

If the lamps run just right the porridge will taste great.

Just right = _________ degrees F.

[Don]

Jim:

First of all, there are two "test modalities" that we use:

1. SLTS (Single Lamps In A Test Stand). When we test a single lamp in a test stand, the "key" is to make the measurement when it has reached a "steady state" condition whereby the lamp is stable. Although we monitor all of the electrical and environmental conditions, the best way we have found to determine when "steady state" has been reached is to make repetitive (@ 30 second intervals) measurements with a "real time" spectroradiometer and a MED/hour meter. When the readings are "stable" we start the Optronics Laboratories 754 spectroradiometer and take the measurement. [Note: We pull three lamps at random from the new and unopened case and make three separate measurements on each lamp.]

2. STU (Standard Test Unit). Since the measurement of an "array of sunlamps" in a STU is designed to replicate the "real world" condition of a tanning salon, we control the "ambient" temperature to 80 degrees (F) plus/minus 3 degrees. [Note: Keep in mind that we are not interested in acrylic or "glass" surface temperature or lamp wall temperature, we are interested in measuring the "output" of the array.] In addition to the Optronics Laboratories 754 spectroradiometer, we (once again) use a "real time" spectroradiometer and a MED/hour meter to measure the "rate of change of change" of the output over the session time. [Note: Although you may not have a spectroradiometer, you can use a Solartech meter (I prefer the MED/hour meter) and "lock down" the "on button" with a clip and watch the change in the reading over the session time. Some of the units change very little during the session time while the change from start to finish with others is quite large.]

I hope this helps.

[Jim Fisher]

we are not interested in acrylic or "glass" surface temperature

Yes.. But most salon owners are.. I know of quite a few salon owners that do not even check out a tanning bed before buying one and then they get it and find out that heat is a major issue .

[Don]

Jim:

That's a different question.

You said that "I know of quite a few salon owners that do not even check out a tanning bed before buying one and then they get it and find out that heat is a major issue." and you are absolutely correct.

The "surface temperature" of the acrylic can be checked by (1) using an inexpensive IR (Infrared) thermometer (Radio Shack sells one for approximately $50.00) that has a "focal distance" of approximately 3 inches; or, (2) the "old fashioned" way, i.e., putting your own butt in the bed. At approximately 115-120 degrees it will feel uncomfortable; at approximately 130-140 degees it will feel "hot" and at aproximately 150-160 degrees there is a chance of mild burning.

What I recommend is to run the bed through 3 or 4 sessions "back to back" and then measure the "surface temperature" by one of the two methods discussed above. That way, you will duplicate what your clients experience on a busy day.

FYI, temperature doesn't have as much affect on LP lamps as it does on HID/hp lamps (where temperature control is critical to performance).

[Jim Fisher]

I know all that.. What I am asking in future testing . Would you please post temperature readings at the acrylics. I would think that you would already have a laser temp reader.